1. Field of the Invention
The present invention relates to an image processing apparatus, a filter acquisition apparatus, an image processing method, a filter acquisition method, a program, and a recording medium, and particularly, to a filter acquisition technique that is usable in an image filtering process and an image filtering process.
2. Description of the Related Art
Various image filtering process techniques such as a filtering process for enhancing image quality or a filtering process for providing a special visual effect have been proposed. For example, a point image restoration process that restores an original image using a filter determined based on a point spread function (PSF) indicating an image deterioration characteristic due to aberration of an imaging lens or the like is known.
For example, JP2011-124692A discloses an image processing method with the purpose of suppressing adverse effects such as noise amplification, wringing, and an occurrence of false colors associated with an image restoration process. According to the image processing method, a first image in which amplitude components and phase components are restored is generated, and a second image in which only phase components are restored is generated. A restoration adjustment image is generated by synthesizing differential information between the first image and the second image with the second image according to a restoration strength adjustment coefficient.
Moreover, JP2011-123589A discloses an image processing method with the purpose of suppressing amplification of noise in a restored image, reducing asymmetrical aberration such as coma aberration and magnification chromatic aberration, and improving sharpness. According to the image processing method, an image restoration filter for reducing phase degradation components of the image is used and a process of restoring only phase degradation components is performed. An edge emphasis process in consideration of an edge portion is performed in amplitude correction associated with noise amplification.